1. Technical Field
Various embodiments of the present disclosure relate generally to voltage supply devices generating voltages for memory cells of semiconductor devices and, more particularly, to voltage supply devices generating voltages for nonvolatile memory cells.
2. Related Art
Semiconductor devices may receive a power supply voltage from an external device to operate. The power supply voltage provided by the external device typically has a constant level. In general, various voltages having different levels are used in operation of a semiconductor device. For example, at least a read voltage, an erase voltage and a program voltage (also, referred to as a write voltage) having different voltage levels are used in the operation of nonvolatile memory (NVM) cells of a nonvolatile memory (NVM) device. Thus, it is generally necessary to supply various different voltages to the NVM cells using a voltage supply device in order to operate the NVM cells.